Systemic drug therapy for metastatic uterine leiomyosarcoma: treatment results from real clinical practice

Background. Currently, adjuvant chemotherapy of choice after surgical treatment of uterine leiomyosarcoma is doxorubicin. The same approach is used for the 1^st line of systemic drug therapy in patients with initially metastatic process, or those who have not previously received adjuvant treatment with anthracyclines. Disseminated forms of metastatic leiomyosarcoma are characterized by unfavorable prognosis, and the options for potentially effective drug treatments are limited.

Aim. To evaluate the efficacy of 1^st and 2^nd line chemotherapy regimens for uterine leiomyosarcoma in a population of patients in real clinical practice.

Materials and methods. The retrospective analysis included 43 patients with histologically verified uterine leiomyosarcoma. The study included patients with primarily localized forms of the disease, who underwent surgical treatment at the 1^st stage (with or without adjuvant chemotherapy), and patients with initially metastatic disease. All patients had a history of 1–2 lines of systemic drug therapy due to disease progression.

Results. The analysis included 43 patients who underwent treatment at the N. N. Blokhin National Medical Research Center of Oncology between 2021 and 2024. The efficacy of the 1^st line was assessed in 35 (81.4 %) patients: the objective response rate reached 17.6 %, and median progression-free survival from the start of the 1^st line was 7.4 months. The efficacy of 2^nd line of therapy was assessed in 18 (41.9 %) patients: the objective response rate was 11.1 %, median progression-free survival from the start of the 1^st line to progression after the 2^nd line was 13.2 months, and median progression-free survival from the start of the 2^nd line to progression after it was 3.3 months.

Conclusion. Analysis of the efficacy of systemic drug therapy for uterine leiomyosarcoma in real clinical practice demonstrates comparable long-term treatment results with data from international literature. Further study of the efficacy of combined adjuvant and 1^st line therapy regimens seems promising.